The federal government is under increasing pressure to make long-awaited changes to the nation's bribery laws following the release of a study revealing worldwide perceptions of the level of corruption in Australia's government sector worsened over the past year. 
The latest international Corruption Perception Index -released by Transparency International, the global civil -society organisation leading the fight against international corruption, showed two-thirds of the 168 countries on the 2015 index scored below 50, on a scale from 0 (perceived to be highly corrupt) to 100 (perceived to be very clean).
The index uses 12 surveys of expert assessment and the views of businesspeople globally to compile its scores.
Denmark took the top spot for the second year running, with North Korea and Somalia the worst performers, scoring just eight points each. The big improvers last year included Greece, Senegal and Britain.
Australia sat alongside Libya, Brazil, Spain and Turkey after suffering the biggest falls in scores over the past four years.
Australia's score fell to 79, down from 85 in 2012, 81 in 2013 and 80 in 2014. It is now ranked 13th out of the 168 countries included in the index - down six positions from 2012.
TI Australia's incoming chairman, Anthony Whealy QC, said the slide was "the result of inaction from successive governments who have failed to address weaknesses in Australia's laws and legal processes".
"The delay in responding to these issues has now made reform critical and a commitment to ramp up efforts to tackle foreign bribery, which has particularly impacted perceptions of Australia, is now urgent," Mr Whealy said.
TI Australia has launched a push to support greater transparency in legislation and regulations to stop political funding rorts and reduce money-laundering and fraud from foreign individuals using Australia as a place to hide money.
Submissions to the Senate Economics Committee's inquiry into foreign bribery closed in   August and the report of its findings is due early this year.
Big companies and government bodies that in recent years have been caught up in bribery and corruption issues include the Reserve Bank, BHP Billiton, AWB and Leighton Holdings.
The government has committed to be part of the Open Government Partnership, a global effort to make governments more open and responsive to the changing needs of citizens. To complete its membership of the OGP, the Australian government has pledged to develop a National Action Plan by the end of   June.
The first stage of the public consultation started in   November to establish a vision for open government in Australia, defining the structure of the Australian Government National Action Plan and sharing the history of open government in Australia."TI Australia welcomes the Turnbull government's move to develop a national Open Government action plan in 2016, and looks forward to working with it on the many issues that must be addressed if we are to improve our corruption perception score and regain leadership on anti-corruption," said TI Australia chief executive Phil Newman.